7

I have a CoreData model that uses SQLite as persistence store. I need to insert large numbers of rows after doing some processing to each record. Is there any way to send those commands to SQLite 

PRAGMA synchronous=OFF
PRAGMA count_changes=OFF
PRAGMA journal_mode=MEMORY
PRAGMA temp_store=MEMORY

I need to speed up the processing time, as it takes couple of hours to complete.

Any hints will be appreciated.

Thanks

محمد الاشرف أنور
  • 302
  • 3
  • 13

1 Answers1

12

You can specify the pragmas when adding your store to the store coordinator:

NSMutableDictionary *pragmaOptions = [NSMutableDictionary dictionary];
[pragmaOptions setObject:@"OFF" forKey:@"synchronous"];
[pragmaOptions setObject:@"OFF" forKey:@"count_changes"];
[pragmaOptions setObject:@"MEMORY" forKey:@"journal_mode"];
[pragmaOptions setObject:@"MEMORY" forKey:@"temp_store"];
NSDictionary *storeOptions =
    [NSDictionary dictionaryWithObject:pragmaOptions forKey:NSSQLitePragmasOption];
NSPersistentStore *store;
NSError *error = nil;
store = [psc addPersistentStoreWithType:NSSQLiteStoreType
            configuration: nil
            URL:url
            options:storeOptions
            error:&error];

(Adapted from Persistent Store Features)

I strongly suggest to also read "Efficiently Importing Data".

Related documentation: NSSQLitePragmasOption Efficiently Importing Data

Christian Kienle
  • 733
  • 1
  • 14
  • 26
  • You should be aware of the consequences the memory mode has: If something bad happens (crash, exception, force quit, ...) you will lose the data which is in the in memory journal. If this is what you want: Go for it. – Christian Kienle Sep 19 '13 at 14:54
  • is there a journal_mode = OFF mode? – Duck Sep 19 '13 at 15:38
  • Yes. journal_mode = OFF. But if I were you I would not use this option either. There are a lot of other things you can do to improve performance when importing data. Playing around with the pragmas is only a last resort. Read the documentation I linked. – Christian Kienle Sep 19 '13 at 17:04